From a clinical standpoint, Dr. Raper is interested in complex gastrointestinal surgical problems. In particular, he has an interest in the management of surgical complications of bariatric surgery. The renaissance of interest in surgical procedures for the treatment of morbid obesity has created new problems in the management of these complex patients.

Dr. Raper also has expertise in complex intestinal, pancreatic, and biliary tract disease. These interests mesh well with the mission of the University of Pennsylvania Health System as a quaternary referral center.

A thirds area of interest is in the surgical repair of large, complex hernias. Such hernias may arise spontaneously or as a result of prior surgical procedures. Re-closure of the abdominal wall after prior surgery can be a challenging problem, especially in the obese individual.